package main

import "fmt"

func main() {
	var sum, _ int = calculate(10, 20)
	fmt.Println("sum : ", sum) //正常输出
	// fmt.Println(" _ : ",_)    //直接报错,无法通过编译
}

func calculate(a int, b int) (int, int) {
	return a + b, a - b
}
